Effect of multiple sides of heated bluff body and heat transfer in a confined region: a computational study

Abstract

The rapid increase in technologies, especially computer chips, increases the demand for highly efficient thermal management systems. The present study carries out a two-dimensional numerical investigation on the effect of the number of sides of a heated cylinder in a highly confined fluid domain. The flow is confined to a blockage ratio of 3. The study is conducted for laminar flow with Reynolds numbers being 50, 100, 150 and 200. Six cylinders are chosen; Square, pentagon, hexagon, circle, dodecagon and hexa-decogan. The simulation is carried out using ANSYS FLUENT 18. SIMPLE algorithm is used to solve the Navier–Stokes equation. The flow and heat transfer characteristics are studied from pressure and temperature contour, viscous drag co-efficient, pressure-drag coefficient, total drag co-efficient, pressure co-efficient, Strouhal number and Nusselt number. As the number of sides increased, a significant difference in flow and heat transfer characteristics is observed at the starting, but all slowly started to converge toward the characteristics of the circular cylinder. The dodecagon cylinder shows better flow and heat transfer performance on average when compared to all the other cylinders.